One strategy is to knock them out using multiplexed CRISPR-based gene editing [80] or other non-viral methods: e.g., the inactivation of PDCD1 in melanoma-reactive CD8+ T cells and fibrosarcoma-reactive polyclonal T cells using TALEN-enhanced T-cell infiltration in the tumor site and tumor control [117]. This evidence concerns the gene PDCD1 and neoplasm.